The invention relates to a bar-type screen cage with profiled screen bars (profile bars) which are spaced apart in circumferential direction so as to form screen slots, wherein on the outside multiple support arrangements, which are spaced apart in axial direction, are fastened by means of welding, which support arrangements can for example be formed by support wires or support rings. Such a bar-type screen cage is known from WO 02/097 190 A1.
From EP 0 958 432 B1 a wire screen product, such as a screen plate or a screen cage is known, which is a resistance-welded screen construct. In this case the support wire is configured with two extensions for introducing a high current density, which noses become deformed, melt and fix the arrangement of support wire and profiled screen cage at two spaced apart defined welding points. This is intended to improve the stability and in particular the bending stability.
From EP 0 929 714 B2 a screen cage construct with a U-shaped reinforcement profile is known. The fixing is accomplished by deformation (embossment or bending) or by welding.
From U.S. Pat. No. 6,589,424 B1 a screen cage construct is known in which the profiled screen bar is positioned in a slotted U-profile part. An energy rich laser beam, which is radially guided from the outside, fixes the profiled screen bar and the U-shaped support wire.
In addition, further screen cage constructs are known from DE 33 27 422 A1, DE 27 47 148 A1 and EP 432 448 A1 in which besides resistance welding a soldering process is additionally used in order to minimize the adverse effect of the weld expulsion associated with resistance welding. During sorting of fiber suspensions the sharp-edged weld expulsion leads to spinnings and the formation of fiber clumps.
All currently known configurations of bar-type screen cages are very cost-intensive and it is in particular difficult to reliably reproduce predetermined slot widths.